화학공학소재연구정보센터
Journal of Physical Chemistry B, Vol.122, No.6, 2040-2045, 2018
Energy Renormalization for Coarse-Graining the Dynamics of a Model Glass-Forming Liquid
Coarse-grained modeling achieves the enhanced computational efficiency required to model glass-forming materials by integrating out "unessential" molecular degrees of freedom, but no effective temperature transferable coarse-graining method currently exists to capture dynamics. We address this fundamental problem through an energy-renormalization scheme, in conjunction with the localization model of relaxation relating the Debye-Waller factor < u(2)> to the structural relaxation time tau. Taking ortho-terphenyl as a model small-molecule glass-forming liquid, we show that preserving < u(2)> (at picosecond time scale) under coarse-graining by renormalizing the cohesive interaction strength allows for quantitative prediction of both short-and long-time dynamics covering the entire temperature range of glass formation. Our findings provide physical insights into the dynamics of cooled liquids and make progress for building temperature-transferable coarse-grained models that predict key properties of glass-forming materials.